We propose a bilayer Kane-Mele-Haldane model that realizes spin-selective higher-order topology and generates spin-polarized corner states without the need for external magnetic fields. A single layer combining intrinsic spin-orbit coupling, a Haldane mass, and a staggered sublattice potential supports a spin-selective quantum anomalous Hall phase, in which only one spin sector carries a nontrivial Chern number. When two layers with distinct parameters are coupled, the bilayer system enters a higher-order topological insulating phase hosting robust spin-polarized corner modes. These corner states are characterized by nonzero spin-resolved winding numbers protected by mirror symmetry, and edge analysis reveals that they originate from Dirac mass domain walls. Furthermore, to provide a spatial-symmetry-independent characterization, we introduce spin-resolved entanglement topological invariants, which independently diagnose the number of protected corner modes in each spin channel. Our results establish a spin-selective extension of the bilayer coupling mechanism, offering a controlled route to engineer spin-resolved higher-order topological states.

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• Kane-Mele model
• Topological insulators
• Two-dimensional electron system